I'll go over, in order, the best games to earn the most mining power from each game. Playing the games as this has been able to keep me in the top 10.000 players fairly easily without even buying a miner yet.
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0. Miners & Playing
First of all, when getting miners. Pick the ones that have the best power for your RLT, good example is El Monstoro as you get 110 Th/s for 99 RLT. Also try to get one of each miner starting out as the mining bonus stacks and adds up, this includes your game power based on how many different miners you have.
Secondly whenever you finish playing a game, when you see your rank update when loading the power. Press the games button and you skip the loading screen. Doing this speed up my game completion alot, so much so that I frequently ran out of games to play waiting for them to refresh.
Try to do all the quest for the free items from the event pass, if you start today you'll most likely be able to do half the pass. The free powerups are a good starter for new players as it gives 1.000 Th/s for a few days, most of the top 10.000 players at the moment are players that got this free buff.
1. Cryptonoid
Avg. time: ~35sec

This game might ring a few plays as it's an old classic. Fairly simple, try to get the ball to bounce up the walls and you'll do alot of damage to the blocks at the top with the most health. When you get a power-up (that isn't the slime) try to target the blocks with the most health and get several blocks at a time. Doing this will speed up your time and the rewards from this game is very high.
2. Dr. Hamster
Avg. time: ~10sec

This is by far the quickest game to beat, I rarely take longer than 10 seconds. Make sure to use the function of dropping the blocks quicker to speed things up. Also target the monster blocks, when those are destroyed you win instantly. This means that you only need 2/3 matches ideally.
3. Token Blaster
Avg. time: ~35sec

Invader, all of these games are classics and this is one of my favorites. Fairly simple, focus on killing the monsters on the sides first and kill all of the ones on the furthest two layers. You can also make use of your ship by slamming it into the side if an enemy comes down to attack you, this only damages you once but instantly kills the attacker. Meaning you get 2 free quick kills, perfect for the flys. Also if you want quicker completions, don't go past stage six as the boss takes longer to kill and requires a full kill for any points.
4. Crypto Hamster
Avg. time: ~30sec

For all four of us who loves jumping. Plan your jumps ahead and avoid aliens, try to use the blaster if possible. However you can use all enemies as a jumping plattform if you land on their head. This can speed up your ascent and should be used on the glassed in ships.
5. Token Surfer
Avg. time: ~40sec

For all us hip skateboarders. Try to aim so you land at either the end or start of a plattform. Save your double jump to avoid the bigger obstacles such as traffic cones or trash cans. You can use the flying ducks for double jumps, do be careful as it is easy to overshoot your jump and miss the next plattform.
6. Flappy Rocket
Avg. time: ~35sec

This one is fairly simple. You can't really speed it up, just stay in between the pipes, candles, blocks? This game's saving grace is that it gives a ok amount of power, unlike all the following games, they give around or under 500 gh/s.
7. Coin-Match
Avg. time: ~25sec

This one is easy if you've played candy crush before. Simply try to make the most use of your time and plan moves ahead of time whenever you make a match. If you can, drop the coins so that you line up a 4 or 5-in-a-row, this speeds up completion alot.
8. 2048 Coins
Avg. time: ~50sec

This one is rather about time instead of skill. Just try to move the coins as often as you can as time is not your friend. Try to keep your highest matched coin to a corner and avoid moving it out. If you try to keep matching your largest coins and keep moving the coins quickly this should go ok, later stages can be harder to complete however.
9. Coin Flip
Avg. time: ~30sec

This one is really simple, flip and match the coins. Try to use some method of remembering which coins you've seen, such as saying them out loud or going in a pattern. This one is basically a free high level game, it is low paying sadly.
10. Coinclick
Avg. time: ~40sec

Point-and-click-adventure-game. Don't click the bombs and click the coins, try to be quick and follow the hamster. Doing that pretty much gives you a win, low payout though.